It takes Jenny some time to notice.
Admittedly, they're in the middle of the slowly encroaching Apocalypse, and she has other things on her mind. Besides, it starts out so slowly and naturally that she feels she can be excused for not paying any attention for a while.
At first, the things that appear after she drops her backpack on the floor of Abbie's guest bedroom make total sense. A toothbrush. A (slightly worn) towel. An (indecently soft) bathrobe. A set of (olive green) pajamas. A set of linens (probably Abbie's).
Then it starts getting - weird. A coffee cup with a picture of overfed cat on it, its rim chipped next to the handle. A battered computer table and a worn chair to go with it, both appearing in her room overnight without any acknowledgment from Abbie. Several tattered paperbacks on the bookshelf: Jenny checks them and finds them to be so familiar, Watership Down and Pride and Prejudice and Wind in the Willows. Tank tops and jeans materialising in her wardrobe, good quality and nice shape, but just - not new. A picture of her and Corbin on the table, in a worn wooden frame. A cup of uneven pencils.
Jenny doesn't know what to make of it. She's used to living out of her bag, and the absence of things doesn't bother her, but this slow accumulation does, due to the sheer randomness of it. It might be gifts, Abbie trying to buy her affection, but who buys one's affection with used things?
It might be a veiled insult, a sly dig at her dependence on Abbie, and at the lack of possessions, and Jenny latches on it for a while, but then lets go. For one thing, Abbie's anger is always direct and vocal, they never had to be passive-aggressive at each other. For another, Jenny's so tired of being angry at Abbie, for whatever transgression; she won't go inventing new reasons.
She waits for things to make sense on their own (more books; more clothes; an afghan for the bed; a set of scented candles, one candle half-burnt). They don't.
Then one day they drag themselves home from a fight with some crazy thing in a forest, too many teeth and too many claws, both exhausted and scratched all to hell and covered in leaves and mud, and when Jenny limps to her room to pick up her bathrobe, there's a toy rabbit on her bed.
She catches her breath, then picks him up and looks closer: it's not a toy of her childhood, but close enough the intent is obvious.
She takes it instead of what she came for, limps back out, and, despite her best intentions, the question comes out as "What the fuck?"
Abbie - blanches, there's no other word for it. She says, instead of explanations or denials, and almost (Abbie!) stammers it: "I'm sorry. I'm sorry. I won't anymore. You can throw out everything, I won't...", and, whoa, Jenny thinks.
She makes herself sound quiet, aiming for 'soothing' and landing somewhere around 'gruff'. "Hey, it's not - I just don't underestand, Abbie."
Abbie looks at her, and then squares her shoulders, and says: "It's - it's really stupid. It's all this magical shit's getting to me, I'm just. You disappeared so quickly, last time. I blinked, and you were not in my life anymore, and I couldn't get you back. I had you, and then I hadn't. "And now I have you again, and you can disappear just as easily, and I'm just trying - I'm trying to pretend you've always been here. Like I could - "
"Like you could keep me this way," Jenny says, understanding dawning. "Like I never left."
Abbie nods, miserable and quiet now, and Jenny looks at her, and at the worn toy in her hand (she called her rabbit Mr. Serious, and told secrets to him, and she and Abbie slept with him snuggled between them, ages five, ages six, ages seven, ages eight), and thinks of all the comfortable, familiar, used things in her room, of this illusion Abbie spent weeks trying clumsily to craft, of Abbie trying to fit her into her life backwards. It's pathetic and weird and sweet and too late and so -
"Hey," she says, and smiles at Abbie, and it almost feels right, "do you think you could find some pictures of me and you, too?"
Abbie's face, in return, is worth it.